Now, we have yet another way to find far-off planets: by looking for inconsistencies in gas flows around them. Other phenomena, however, could also account for these tantalizing features.
The scientists detailed their discoveries in 2 documents released Wednesday in the journal Astrophysical Journal Letters.
Gas giants are born out of a disk filled with hydrogen gas, trace compounds such as carbon monoxide and tiny particulate matter called dust, which is smaller than a single grain of sand.
Richard Teague, an astronomer at the University of MI, took a slightly different approach: His team measured variations in the gas's velocity, leading them to two patterns, located approximately 80 AU and 140 AU from the star.
The opening is based on their analysis of observations with ALMA, the young star HD 163296, located approximately 330 light years from Earth in the constellation Sagittarius.
Scientists have found a trio baby planets using a new technique of spotting unusual gas motion around developing stars.
"We looked at the localized, small-scale motion of gas in a star's protoplanetary disk".
More than a decade ago, astronomers discovered the first planets around other stars by zeroing in on a star and observing whether it "wobbles", as it is affected by the gravitational pull of an orbiting planet. All three bodies carried the same mass as that of Jupiter. Any odd movements in the flow of the gas were a sign that it was in contact with a massive object. This revealed the impact of multiple planets on the gas motion nearer to the star.
ALMA's stunning images of HD 163296 and other similar systems have revealed intriguing patterns of concentric rings and gaps within protoplanetary disks. The rings and gaps in these discs provide intriguing circumstantial evidence for the presence of protoplanets .
ALMA image of the protoplanetary disk surrounding the young star HD 163296, as seen in dust.
All three exoplanets reside within the protoplanetary disk, and that's how the researchers managed to find them. This finding seems to confirm our theories about the formation of planets.
ALMA's fantastic resolution enabled the researchers to measure carbon monoxide's velocity patterns throughout the disk.
"The precision is mind boggling", said coauthor Til Birnstiel of the University Observatory of Munich.
This was caused by the protoplanets changing the density of the gas near their orbits which subsequently changes the pressure of the gas and its velocity.
"By having two independent teams simultaneously arrive at the same conclusions really lends weight to the result", Teague said. The technique is particularly promising for pinpointing very young planets - the kind of observations that could provide invaluable insight into how our solar system and planet Earth formed.
By refining this method, the teams hope to better understand how atmospheres are formed and which elements and molecules are incorporated into a planet from birth.
This significant finding was presented in more details by two distinct research reports, both issued today in the Astrophysical Journal Letters.